Inhaled medicaments are commonly prescribed to patients for treating diseases such as asthma and viral induced wheeze. Inhaled medicaments may be administered via a number of means, including metered dose inhalers (‘MDIs’), and nebulisers. MDIs are the most commonly prescribed means for administering inhaled medicaments.
In order to properly use an MDI, a number of coordinated actions are required (pressing down on the inhaler, breathing in deeply as the medication is released, holding your breath and exhaling). Some patients, for example the very young, elderly or disabled, have difficulty completing the required actions in the correct order and at the correct times.
Patients who experience difficulty using an MDI are commonly provided with a spacer device. Spacer devices connect a drug delivery canister (for example, an MDI) to a mask or mouthpiece. Pressing of the drug canister releases the drug into a chamber of the spacer device. The medicament is held within the chamber by a valve, which is opened upon inhalation, allowing the patient to inhale the treatment in his own time through the mask. Cessation of inhalation causes closure of the valve to keep the remaining drug in the chamber of the spacer device.
Use of the spacer device avoids timing issues experienced with MDIs. Indeed, a patient is generally encouraged to breathe “normally” when using a spacer device, rather than to adopt a particular, abnormal, breathing pattern. Further, aerosol is generally issued to the patient from the spacer device more slowly than when issued directly from the MDI, resulting in less of the drug impacting on the back of the mouth and more of the drug reaching the lungs of the patient. Because of this, less medication is needed for an effective dose to reach the lungs, and there are fewer negative side effects, for example from corticosteroid residue in the mouth.
For children, spacer devices are particularly useful, allowing them to gain the benefit of inhaled drugs in a way that they can use at home, without the use of hospital nebulisers and masks. In fact, studies have shown that when used correctly, these devices can match the efficacy of hospital nebulisers in treatment of asthmatic children.
Spacer devices, do however, suffer from a number of problems which can limit their effectiveness. For example, in order to use a spacer device correctly, the patient is required to make an effective seal with the mask. A poor seal will not allow efficient drug delivery. The quality of the seal may be assessed by a parent/supervisor watching a valve of the spacer device to ensure that the valve is moving and by listening for an accompanying sound. The valves, however, are small, such that assessing the quality of the seal this way is often difficult, especially at night.
Further, once a correct seal is made, the patient is required to take multiple separate breaths to inhale the drug. This process may itself need to be repeated multiple times and for severe attacks may need to be performed hourly or two hourly. The difficulty faced by some patients is therefore increased just at the moment when an effective treatment is most in need. For children, such repetition often leads boredom, distraction and an unwillingness to participate, especially when tired or unwell. Furthermore placing a mask over the face of a patient can potentially cause further distress in an already stressful and difficult situation. Such disadvantages can hinder efforts to encourage a patient to adopt their normal breathing pattern, which is required to achieve the most effective administration of the medicament.
It is an object of the present invention to obviate or mitigate one or more of the problems outlined above.
US 2014/0106324 discloses an inhalation training system. However, this system does not assist a patient, particularly children, in monitoring inhalation from a respiratory device, such as an in inhaler.